formaldehyde

noun

form·​al·​de·​hyde fȯr-ˈmal-də-ˌhīd 

fər-

: a colorless pungent irritating gas CH₂O used chiefly in aqueous solution as a disinfectant and preservative and in chemical synthesis

Examples of formaldehyde in a Sentence

Recent Examples on the Web

In addition, science on air pollution and formaldehyde has improved since then, the suit alleges. — Theresa Clift, Sacbee.com, 30 July 2026

Turns out, yes, some did clean volatile organic compounds (VOCs) like formaldehyde out of the air when they were placed in small, airtight containers. — Leanne Potts, Better Homes & Gardens, 30 July 2026

Parabens, phthalates and formaldehyde-releasing preservatives are other ingredients to avoid. — Bestreviews, Mercury News, 14 July 2026

Some states are running ahead of the federal government on this front, with Washington banning the use of formaldehyde-releasing chemicals in 2025. — David Faris, TheWeek, 12 June 2026

Word History

Etymology

International Scientific Vocabulary form- + aldehyde

First Known Use

1872, in the meaning defined above

Phrases Containing formaldehyde

• urea-formaldehyde

Rhymes for formaldehyde

• acetamide
• acetonide
• acidified
• antimonide
• beatified
• benzaldehyde
• borohydride
• chalcogenide
• commodified
• decalcified
• declassified
• disaccharide

Kids Definition

formaldehyde

noun

form·​al·​de·​hyde fȯr-ˈmal-də-ˌhīd 

fər-

: a colorless gas that consists of carbon, hydrogen, and oxygen, has a sharp irritating odor, and when dissolved in water is used to disinfect or to prevent decay

Medical Definition

formaldehyde

noun

form·​al·​de·​hyde fȯr-ˈmal-də-ˌhīd, fər- 

: a colorless pungent irritating gas CH₂O used chiefly as a disinfectant and preservative and in chemical synthesis